Blogs

LS-DYNA is historically known as the world's best explicit analysis code or the leader in the finite element analysis of nonlinear transient events. During the last ten years, LSTC (the manufacturer of LS-DYNA) has heavily invested in the development of its implicit anlaysis capabilities. Today, LS-DYNA can seamlessly handle complex, nonlinear analyses from static (implicit) to transient (explicit). Predictive Engineering has developed training course materials that covers both the implicit and explicit sides of the code. It was with pleasure that we taught a course in Shanghai, China to 27 students from industry and academia. This three day LS-DYNA training course was focused on LS-DYNA's implicit analysis capabilities from linear, elastic static stress analysis to static nonlinear analysis to fully, transient nonlinear analysis. The course finished with a half-day training on the linear dynamics capabilites of LS-DYNA.

It's been a busy year for Predictive Engineering. We'll take our secret projects to the grave, but we're excited to share two recent analysis projects utilizing LS-DYNA. See step-by-step figures of the process along with video examples and PDF download.

In this LS-DYNA FEA consulting services work, the objective was to limit the design and schedule exposure of a new design. One can think of this as FEA insurance; that is, it is must less expensive and faster to virtually test than to destroy prototypes on a 16g sled test. Experimentally, a 50% percentile dummy or anthropomorphic test device (ATD) is strapped into the chair and then subjected to a 16g acceleration pulse with a half-sine pulse width of 0.18 second. The test procedure is well defined under 14 CFR Part 25.562, Amendment 25-64 and JAR Part 25.562 with guidance given under SAE AS8049 Rev. A and for the ATD under 49 CFR 572. READ MORE

Every year, Predictive Engineering attends an LS-DYNA Conference, this year it was in Dearborn, MI and next year, it’ll be in Koblenz, Germany. The technical sessions covered a broad range of topics from "How To's" to new numerical algorithms to validation work between experimentalists and theoreticians. For me personally, these were the three stand-out talks:

(i) Modeling & Simulation Challenges at the Interface between Man and Machine: Medical Devices by Dr. M. Palmer
(ii) Modeling of a Cross-Ply Thermoplastic for Thermoforming of Composite Sheets in LS-DYNA by K. White and
(iii) An Enhance Assumed Strain (EAS) Solid Element for Nonlinear Implicit Analysis by T. Borrvall.

The first paper was by Medtronic and the background gossip is that they are moving away from other commercial solvers to focus on just LS-DYNA due to its multi-physics capabilities and especially its strong nonlinear implicit performance. The second paper was a stunner and showed how thermoplastics can easily reach their glass transition temperature under moderate strain rates. In essence, whenever composites are simulated under dynamic environments, one should consider temperature effects on the resin and how it will lower its elasticity. The third paper was just plain fun mechanics and how LS-DYNA is continually expanding its capabilities in the implicit arena.